document.write( "Question 481988: I am very confused with Algebra as a whole If someone can please help me using the substitution method with each step I would greatly appreciate it. 6x-2y=12 2x+2y=8 \n" ); document.write( "
Algebra.Com's Answer #330008 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "Start with the given system of equations:\r
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\n" ); document.write( "\n" ); document.write( "\"system%286x-2y=12%2C2x%2B2y=8%29\"\r
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\n" ); document.write( "\n" ); document.write( "Now in order to solve this system by using substitution, we need to solve (or isolate) one variable. I'm going to solve for y.\r
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\n" ); document.write( "\n" ); document.write( "So let's isolate y in the second equation\r
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\n" ); document.write( "\n" ); document.write( "\"2x%2B2y=8\" Start with the second equation\r
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\n" ); document.write( "\n" ); document.write( "\"2y=8-2x\" Subtract \"2x\" from both sides\r
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\n" ); document.write( "\n" ); document.write( "\"2y=-2x%2B8\" Rearrange the equation\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28-2x%2B8%29%2F%282%29\" Divide both sides by \"2\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=%28%28-2%29%2F%282%29%29x%2B%288%29%2F%282%29\" Break up the fraction\r
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\n" ); document.write( "\n" ); document.write( "\"y=-x%2B4\" Reduce\r
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\n" ); document.write( "\n" ); document.write( "Since \"y=-x%2B4\", we can now replace each \"y\" in the first equation with \"-x%2B4\" to solve for \"x\"\r
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\n" ); document.write( "\n" ); document.write( "\"6x-2highlight%28%28-x%2B4%29%29=12\" Plug in \"y=-x%2B4\" into the first equation. In other words, replace each \"y\" with \"-x%2B4\". Notice we've eliminated the \"y\" variables. So we now have a simple equation with one unknown.\r
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\n" ); document.write( "\n" ); document.write( "\"6x%2B%28-2%29%28-1%29x%2B%28-2%29%284%29=12\" Distribute \"-2\" to \"-x%2B4\"\r
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\n" ); document.write( "\n" ); document.write( "\"6x%2B2x-8=12\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"8x-8=12\" Combine like terms on the left side\r
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\n" ); document.write( "\n" ); document.write( "\"8x=12%2B8\"Add 8 to both sides\r
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\n" ); document.write( "\n" ); document.write( "\"8x=20\" Combine like terms on the right side\r
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\n" ); document.write( "\n" ); document.write( "\"x=%2820%29%2F%288%29\" Divide both sides by 8 to isolate x\r
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\n" ); document.write( "\n" ); document.write( "\"x=5%2F2\" Reduce\r
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\n" ); document.write( "\n" ); document.write( "-----------------First Answer------------------------------\r
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\n" ); document.write( "\n" ); document.write( "So the first part of our answer is: \"x=5%2F2\"\r
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\n" ); document.write( "\n" ); document.write( "Since we know that \"x=5%2F2\" we can plug it into the equation \"y=-x%2B4\" (remember we previously solved for \"y\" in the second equation).\r
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\n" ); document.write( "\n" ); document.write( "\"y=-x%2B4\" Start with the equation where \"y\" was previously isolated.\r
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\n" ); document.write( "\n" ); document.write( "\"y=-5%2F2%2B4\" Plug in \"x=5%2F2\"\r
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\n" ); document.write( "\n" ); document.write( "\"y=3%2F2\" Combine like terms (note: if you need help with fractions, check out this solver)\r
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\n" ); document.write( "\n" ); document.write( "-----------------Second Answer------------------------------\r
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\n" ); document.write( "\n" ); document.write( "So the second part of our answer is: \"y=3%2F2\"\r
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\n" ); document.write( "\n" ); document.write( "-----------------Summary------------------------------\r
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\n" ); document.write( "\n" ); document.write( "So our answers are:\r
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\n" ); document.write( "\n" ); document.write( "\"x=5%2F2\" and \"y=3%2F2\"\r
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\n" ); document.write( "\n" ); document.write( "which form the point \r
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